Systems and methods for printing components using additive manufacturing

ABSTRACT

In one embodiment of the present disclosure, a method of forming a part using additive manufacturing may include receiving, at a computer numeric controlled (CNC) machine, a computer aided design (CAD) model of the part. The method may further include dividing the CAD model into plurality of sections. The method may further include slicing each of the plurality of sections into a plurality of layers. Each section may include a distinct set of print parameters. The method may further include depositing a flowable material onto a worktable according the set of print parameters for each section of the plurality of sections to manufacture the part.

TECHNICAL FIELD

Aspects of the present disclosure relate to apparatus and methods forfabricating components. In some instances, aspects of the presentdisclosure relate to apparatus and methods for fabricating components(such as, e.g., automobile parts, medical devices, machine components,consumer products, etc.) via additive manufacturing techniques orprocesses, such as, e.g., three-dimensional (3D) printing.

BACKGROUND

Additive manufacturing techniques and processes generally involve thebuildup of one or more materials, e.g., layering, to make a net or nearnet shape (NNS) object, in contrast to subtractive manufacturingmethods. Though “additive manufacturing” is an industry standard term(ASTM F2792), additive manufacturing encompasses various manufacturingand prototyping techniques known under a variety of names, including,e.g., freeform fabrication, 3D printing, rapid prototyping/tooling, etc.Additive manufacturing techniques may be used to fabricate simple orcomplex components from a wide variety of materials. For example, afreestanding object may be fabricated from a computer-aided design (CAD)model.

A particular type of additive manufacturing is commonly known as 3Dprinting. One such process commonly referred to as Fused DepositionModeling (FDM) or Fused Layer Modeling (FLM) comprises melting a thinlayer of thermoplastic material, and applying this material in layers toproduce a final part. This is commonly accomplished by passing acontinuous thin filament of thermoplastic material through a heatednozzle, or by passing thermoplastic material into an extruder with anattached nozzle, which melts and applies the melted thermoplasticmaterial to a structure being printed, building up the structure. Themelted thermoplastic material may be applied to the existing structurein layers, melting and fusing with the existing material (e.g., thepreviously deposited layers of the melted thermoplastic material of thestructure), to produce a solid finished part.

The filament used in the aforementioned process may be produced, forexample, using an extruder, which may include a steel extruder screwconfigured to rotate inside of a heated steel barrel. Thermoplasticmaterial in the form of small pellets may be introduced into one end ofthe rotating screw. Friction from the rotating screw, combined with heatfrom the barrel may soften the thermoplastic material, which may then beforced under pressure through a small round opening in a die that isattached to the front of the extruder barrel. In doing so, a “string” ofmaterial may be extruded, after which the extruded string of materialmay be cooled and coiled up for use in a 3D printer or other additivemanufacturing system.

Melting a thin filament of material in order to 3D print an item may bea slow process, which may be suitable for producing relatively smallitems or a limited number of items. The melted filament approach to 3Dprinting may be too slow to manufacture large items. However, thefundamental process of 3D printing using molten thermoplastic materialsmay offer advantages for the manufacture of larger parts or a largernumber of items.

In some instances, the process of 3D printing a part may involve atwo-step process. This two-step process, commonly referred to asnear-net-shape, may begin by printing a part to a size slightly largerthan needed, e.g., printing using a larger bead, then machining,milling, or routing the part to the final size and shape. The additionaltime required to trim the part to a final size may be compensated for bythe faster printing process.

A common method of additive manufacturing, or 3D printing, may includeforming and extruding a bead of flowable material (e.g., moltenthermoplastic), applying the bead of material in a strata of layers toform a facsimile of an article, and machining the facsimile to producean end product. Such a process may be achieved using an extruder mountedon a computer numeric controlled (CNC) machine with controlled motionalong at least the x-, y-, and z-axes. In some cases, the flowablematerial, such as, e.g., molten thermoplastic material, may be infusedwith a reinforcing material (e.g., strands of fiber or a combination ofmaterials) to enhance the material's strength.

The flowable material, while generally hot and pliable, may be depositedupon a substrate (e.g., a mold), pressed down or otherwise flattened tosome extent, and leveled to a consistent thickness, e.g., by means of atangentially compensated roller. The roller may be mounted in or on arotatable carriage, which may be operable to maintain the roller in anorientation tangential, e.g., perpendicular, to the deposited material(e.g., a print bead or beads). In some embodiments, the roller may besmooth and/or solid. The flattening process may aid in fusing a newlayer of the flowable material to the previously deposited layer of theflowable material. The deposition process may be repeated so that eachsuccessive layer of flowable material is deposited upon an existinglayer to build up and manufacture a desired component structure. In someinstances, an oscillating plate may be used to flatten the bead offlowable material to a desired thickness, thus effecting fusion to thepreviously deposited layer of flowable material. In order to achieveproper bonding between printed layers, the temperature of the layerbeing printed upon must cool, and solidify sufficiently to support thepressures generated by the application of a new layer. The layer beingprinted upon must also be warm enough to fuse with the new layer. Whenexecuted properly, the new layer of flowable material may be depositedat a temperature sufficient to allow the new layer to melt and fuse withthe new layer, thus producing a solid part.

Some CNC programs may generate a print program including a tool path foreach layer using a “slicing process”. The slicing process may divide or“slice” a computer model of the part to be printed into layers.Typically, slicing processes divide a part into layers havingapproximately the same print parameters. For example, the slicingprocess may use a constant thickness for each layer, e.g., a thicknessapproximately equal to the thickness of the print bead. After dividingthe part into layers, a tool path for each layer is generated such thatthe tool path guides the beads of material being deposited to reproducethe shape of each layer. That is, the tool path directs movement of anozzle for depositing the material in a layer.

During the slicing process, a number of print parameters for each layermay be taken into account such as, e.g., a width and/or a thickness ofprint bead, a width of the perimeter of the part, a start location and astop location of an applicator head including the nozzle, an infillpattern, and a print speed. For example, slicing processes typicallydivide parts into layers having constant print parameters. Such slicingprocesses may be inefficient and limited. For example, by maintainingall printing parameters constant for every layer of a part, typicalslicing programs cannot optimize print parameters of different sectionsof a part. It may be desirable, however, to produce a part usingdifferent print parameters at separate areas of the part, e.g.,printing, an outside perimeter of the part with print beads havingdimensions different from the print beads used to form the internalstructures of the part.

SUMMARY

Aspects of the present disclosure relate to, among other things, methodsand apparatus for fabricating components via additive manufacturing or3D printing techniques. Each of the aspects disclosed herein may includeone or more of the features described in connection with any of theother disclosed aspects. In one aspect, the present disclosure relatesto systems and methods for dividing a model of a part into layers, eachlayer including print parameters, and using additive manufacturing tocreate the part.

When preparing a CAD model of a part to be printed, traditional methodsmay include generating models of an outside shape and any interiorstructures of the part. The models for the outside shape and theinterior structures may be generated separately. Each of the models maythen divided, or sliced, into a number of layers. Subsequently, toolpaths may be determined for the layers to develop a printing program orprocess to manufacture the sections of the outside shape and theinterior structures. After printing, each section separately, thesections may be assembled into the part. After assembly, a final printprocess may be executed to complete the part.

Alternatively, according to the present disclosure, a slicing processmay divide the part to be printed into multiple sections, each with itsown unique print parameters, before slicing the sections into layers.Each of these sections may be configured to be printed as part of asingle printing process. In some examples, the sections may be processedby the slicing process so that the sections to fuse together whenprinted.

The print process developed from such a slicing process may begin byprinting on a workpiece a first layer of a first section according toone or more print parameters. Then a first layer of a second section maybe printed according to print parameters different and/or distinct fromthose used to print the first layer of the first section. The printingprocess may continue to repeat the steps of adjusting the printingparameters and printing a first layer for any subsequent sections. Uponcompleting the printing of the first layer of each section, the stepsmay be repeated for any additional layers of each section until allsections have been printed. Additionally, or alternatively, the printingprocess developed from the slicing process may print the layers of thefirst section interspersed with printing layers of the second section,e.g., one or more layers of the first section may be printed beforeprinting a layer of the second piece.

A print position of each section of the part processed by the slicingprocess may be adjusted so that areas where the sections are designed tofuse together are located in sufficient proximity for the print beads ofeach section to overlap sufficiently to joining the sections together.

In some examples, a section processed by the slicing process may belocated at a distance above the worktable instead of directly on theworktable. For example, an elevated section may be located atop a basesection. In this case, the first layer of the elevated section may notbe printed until a collective height of the layers that have beenprinted reaches the height above the worktable equal to the first layerof the elevated section. In this way, the base section (and anyintervening sections) may be printed until the layers of the basesection (and any intervening sections) reach the vertical location ofthe elevated section, and then the elevated section may be printed ontop of the base section. By locating sections at varying heights abovethe worktable, the slicing process may increase the ability to optimizethe printing process for each section.

By processing parts section-by-section the slicing process may increasethe ability to utilize advanced design tools when positioning a sectionfor printing. For example, a wall of one (e.g., a first) section mayserve as a wall of a second section, thereby eliminating the requirementof positioning a wall of the first section sufficiently adjacent to awall of the second section so that the walls mesh together.

In one embodiment of the present disclosure, a method of forming a partusing additive manufacturing may include receiving, at a computernumeric controlled (CNC) machine, a computer aided design (CAD) model ofthe part. The method may further include dividing the CAD model intoplurality of sections. The method may further include slicing each ofthe plurality of sections into a plurality of layers. Each section mayinclude a distinct set of print parameters. The method may furtherinclude depositing a flowable material onto a worktable according theset of print parameters for each section of the of the plurality ofsections to manufacture the part.

In an additional or alternative embodiment of the present disclosure, amethod of forming a part using additive manufacturing may includereceiving at an electronic device, a computer aided design (CAD) modelof the part. The method may further include dividing the CAD model intoa first section and a second section. The method may further includeselecting a first set of print parameters for the first section. Themethod may further include selecting a second set of print parametersfor the second section. The first set of print parameters may bedifferent from the second set of print parameters. The method mayfurther include slicing the first section into a first set of layers andslicing the second section into a second set of layers. The method mayfurther include depositing a flowable material onto a surface accordingthe first set of print parameters and the second set of printparameters. The first set of layers and the second set of layers may bedeposited so as to be interspersed with one another.

In an additional or alternative embodiment of the present disclosure, amethod of forming a part using additive manufacturing may includereceiving at an electronic device, a computer aided design (CAD) modelof the part. The method may further include dividing the CAD model intoa plurality of sections. The method may further include slicing each ofthe plurality of sections into a plurality of layers. Each layer mayhave a plurality of print parameters. The method may further includedepositing a flowable material onto a substrate according to theplurality of print parameters for each of the plurality of layers. Theplurality of sections may include a first section and a second section.The first section and the second section may each include a set oflayers of the plurality of layers. The print parameters of the set oflayers of the first section may differ from the print parameters of theset of layers of the second section.

As used herein, the terms “comprises,” “comprising,” or any othervariation thereof, are intended to cover a non-exclusive inclusion, suchas a process, method, article, or apparatus. The term “exemplary” isused in the sense of “example,” rather than “ideal.” As used herein, theterms “about,” “generally,” “substantially,” and “approximately,”indicate a range of values within +/−5% of the stated value unlessotherwise stated. As used herein, the term “part” refers to a finishedproduct of the printing process. Each part may comprise one or moresections. As used herein the term “section” refers to a portion ordivision of a part. For example a section may be a plurality of layersof a part, a quadrant, hemisphere, or other division of the part, aninternal structure of a part, or an outside structure of a part.

It may be understood that both the foregoing general description and thefollowing detailed description are exemplary and explanatory only andare not restrictive of the disclosure, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate exemplary aspects of the presentdisclosure and together with the description, serve to explain theprinciples of the disclosure.

FIG. 1 is a perspective view of an exemplary CNC machine operablepursuant to an additive manufacturing process to form articles or parts,according to an aspect of the present disclosure;

FIG. 2 is an enlarged perspective view of an exemplary carrier andapplicator head assembly of the exemplary CNC machine shown in FIG. 1;

FIG. 3 is an enlarged cutaway view of an exemplary applicator headassembly shown in FIG. 2;

FIG. 4 is an exemplary screen shot of a graphical user interface forselection of a toolpath type for use in the slicing process;

FIG. 5 is an exemplary screen shot of a graphical user interfaceprompting the input of print parameters of a geometry subcategory;

FIG. 6 is a perspective view of an exemplary part manufactured using aprinting process generated by the slicing process of the presentdisclosure;

FIG. 7A is a perspective view of an additional exemplary partmanufactured using a printing process generated by the slicing processof the present disclosure;

FIG. 7B is an exploded view of the exemplary part of FIG. 7A,illustrating the various subsections thereof;

FIG. 8 is an exemplary screen shot of a graphical user interfaceprompting input of print parameters of the toolpath subcategory of thegeneral category;

FIG. 9 is an exemplary screen shot of a graphical user interfaceprompting input of print parameters of the process subcategory of thegeneral category;

FIG. 10 is an exemplary screen shot of a graphical user interfaceprompting input of print parameters of the tool subcategory of thegeneral category;

FIG. 11 is an exemplary screen shot of a graphical user interfaceprompting input of print parameters of a passes subcategory of aboundary category;

FIG. 12 is an exemplary screen shot of a graphical user interfaceprompting input of print parameters of a process subcategory of aboundary category;

FIG. 13 is an exemplary screen shot of a graphical user interfaceprompting input of print parameters of a bead geometry subcategory ofthe boundary category;

FIG. 14 is an exemplary screen shot of a graphical user interfaceprompting input of print parameters of the passes subcategory of a fillcategory;

FIG. 15 is a top view diagram of an exemplary fill path generated usinga one-way fill style;

FIG. 16 is a top view diagram of an exemplary fill path generated usinga simple zigzag fill style;

FIG. 17 is a top view diagram of an exemplary fill path generated usinga smart zigzag fill style;

FIG. 18 is a top view diagram of an exemplary fill path generated usinga smart zigzag constant overlap fill style;

FIG. 19 is a top view diagram of an exemplary fill path generated usinga sparse zigzag fill style;

FIG. 20 is an exemplary screen shot of a graphical user interface forthe input of fill style parameters; and

FIG. 21 is a flowchart of a method of executing the slicing process andmanufacturing a part.

DETAILED DESCRIPTION

The present disclosure is drawn to, among other things, methods andapparatus for fabricating components, parts, or articles via additivemanufacturing such as, e.g., 3D printing. Specifically, the methods andapparatus described herein may be drawn to a method of dividing a partinto sections and layers.

For purposes of brevity, the methods and apparatus described herein willbe discussed in connection with the fabrication of parts fromthermoplastic materials. However, those of ordinary skill in the artwill readily recognize that the disclosed apparatus and methods may beused with any flowable material suitable for additive manufacturing.

Referring to FIG. 1, there is illustrated a CNC machine 1 embodyingaspects of the present disclosure. CNC machine 1 may include acontroller 100 operatively connected to CNC machine 1 for displacing anapplicator head 43 (see FIG. 2) along a longitudinal line of travel, orx-axis, a transverse line of travel, or a y-axis, and a vertical line oftravel, or z-axis, in accordance with a program, (e.g., a print programor process) inputted or loaded into the controller 100 for performing anadditive manufacturing process to form a desired component or part, aswill be described in further detail below. Controller 100 may include adisplay 101 (e.g., screen) and an input portion 102, as schematicallyillustrated in FIG. 1. Optionally, input portion 102 may include one ormore of a keyboard, buttons, joystick, mouse, or the like, for entry ofdata by a user. Optionally, display 101 may be a touch screen display inwhich data and/or user selections may be directly input to controller100. In such a case, controller 100 may not include input portion 102.

CNC machine 1 may be configured to print or otherwise build 3D partsfrom digital representations of the 3D parts (e.g., AMF and STL formatfiles). For example, in an extrusion-based additive manufacturing system(e.g., a 3D printing machine), a 3D part may be printed from a digitalrepresentation of the 3D part in a layer-by-layer manner by extruding aflowable material (e.g., thermoplastic material with or withoutreinforcements). With reference to FIG. 2, the flowable material may beextruded through an extrusion tip or nozzle 51 carried by and applicatorhead 43 of the CNC machine 1, and the flowable material may be depositedas a sequence of beads or layers on a substrate in an x-y plane. Theextruded, flowable material may fuse to a previously deposited layer ofmaterial and may solidify upon a drop (e.g., decrease) in temperature.The position of applicator head 43 relative to the substrate may then beincrementally advanced along a z-axis (perpendicular to the x-y plane),and the process may then be repeated to form a 3D part resembling thedigital representation.

CNC machine 1, as shown in FIG. 1, includes a bed 20 provided with apair of transversely spaced side walls 21 and 22, a printing gantry 23and a trimming gantry 36 supported on opposing side walls 21 and 22, acarriage 24 mounted on printing gantry 23, a carrier 25 mounted oncarriage 24, an extruder 61 having and extruder screw (not shown), andthe applicator head (also referred herein as an applicator assembly) 43mounted on carrier 25. Located on bed 20 between side walls 21 and 22 isa worktable 27 provided with a support surface. The support surface maybe disposed in an x-y plane and may be fixed, or displaceable, along anx-axis and/or a y-axis. For example, in a displaceable version,worktable 27 may be displaceable along a set of rails mounted to bed 20.Displacement of worktable 27 may be achieved using one or moreservomotors and one or more of guide rails mounted on bed 20 andoperatively connected to worktable 27. Printing gantry 23 is disposedalong the y-axis, supported on side walls 21 and 22. In FIG. 1, printinggantry 23 is mounted on the set of guide rails 28 and 29, which arelocated along a top surface of side walls 21 and 22.

Printing gantry 23 may either be fixedly or displaceably mounted, and insome aspects, printing gantry 23 may be disposed along the x-axis. In anexemplary displaceable version, one or more servomotors may controlmovement of printing gantry 23. For example, one or more servomotors maybe mounted on printing gantry 23 and operatively connected to tracks,e.g., guide rails 28, 29, provided on the side walls 21 and 22 of bed20.

Carriage 24 is supported on printing gantry 23 and is provided with asupport member 30 mounted on and displaceable along one or more guiderails 31, 32 and 33 provided on printing gantry 23. Carriage 24 may bedisplaceable along a y-axis on one or more guide rails 31, 32 and 33 bya servomotor mounted on the printing gantry 23 and operatively connectedto support member 30. Carrier 25 is mounted on one or more verticallydisposed guide rails 34 and 35 supported on carriage 24 for displacementof carrier 25 relative to carriage 24 along the z-axis. Carrier 25 maybe displaceable along the z-axis by a servomotor mounted on carriage 24and operatively connected to carrier 25.

As best shown in FIG. 2, also fixedly mounted to the bottom of carrier25) is a positive displacement gear pump 62 (e.g., melt pump), which maybe driven by a servomotor 63, through a gearbox 64. Said gear pump 62receives molten plastic from extruder 61, shown in FIG. 1. A compressionroller 59, rotatable about a nonrotatable (e.g., fixed) axle 73, forcompressing deposited flowable material (e.g., thermoplastic material)may be mounted on a carrier bracket 47. Roller 59 may be movably mountedon carrier bracket 47, for example, rotatably or pivotably mounted.Roller 59 may be mounted so that a center portion of roller 59 isaligned with a nozzle 51 of applicator head 43, and roller 59 may beoriented tangentially to nozzle 51. Roller 59 may be mounted relative tonozzle 51 so that material, e.g., one or more beads of flowable material(such as thermoplastic resins), discharged from nozzle 51 are smoothed,flattened, leveled, and/or compressed by roller 59, as depicted in FIG.3. One or more servomotors 60 may be configured to move, e.g.,rotationally displace, carrier bracket 47 via a pulley 56 and belt 65arrangement. In some embodiments, carrier bracket 47 may be rotationallydisplaced via a sprocket and drive-chain arrangement (not shown), or byany other suitable mechanism.

With continuing reference to FIG. 3, applicator head 43 may include ahousing 46 having a rotary union mounted therein. Such a rotary unionmay include an inner hub 76 rotatably mounted within and relative to anouter housing 75. For example, inner hub 76 may rotate about alongitudinal axis thereof relative to outer housing 75 via one or moreroller bearings 49. Carrier bracket 47 may be mounted, e.g., fixedlymounted to inner hub 76, journaled in roller bearing 49. Roller bearing49 may allow roller 59 to rotate about nozzle 51.

As shown in FIGS. 2-3, an oversized molten bead of a material 53 (e.g.,a thermoplastic material) under pressure from a source disposed oncarrier 25 (e.g., one or more of extruder 61 and an associated polymeror gear pump 62) may be flowed to applicator head 43, which may befixedly (or removably) connected to, and in communication with nozzle51. In use, material 53 (e.g., melted thermoplastic material) may beheated sufficiently to form a large molten bead thereof, which may bedelivered through applicator nozzle 51 to form multiple rows ofdeposited material 53 on a surface of worktable 27. In some embodiments,beads of molten material deposited by nozzle 51 may be substantiallyround in shape prior to being compressed by roller 59. Exemplary largebeads may range in size from approximately 0.4 inches to over 1 inch indiameter. For example, a 0.5 inch bead may be deposited by nozzle 51 andthen flattened by roller 59 to a layer approximately 0.2 inches thick byapproximately 0.83 inches wide. Such large beads of molten material maybe flattened, leveled, smoothed, and/or fused to adjoining layers byroller 59.

As mentioned above, CNC machine 1 may be controlled via a program, e.g.a print program to produce a part. The print program may be part of, orgenerated from, a slicing process.

The slicing process may receive a CAD model (or models) of the part tobe printed and slice the part into sections having a plurality oflayers, each section having their own print properties, for printing.The CAD model may be a 3D or 2D representation of the part to beprinted. In some examples, the CAD model may include a model of anoutside shape of the part and separate models of each interior structureof the part. The slicing process may simplify the CAD model which mayallow the print process to be optimized. In some aspects of the presentdisclosure, the part is processed by the slicing process as multiplesections, each section having unique print parameters. These sectionsmay be printed so that the individual sections or sections join togetherto form the part. The slicing process may assemble the sections and/orlayers into a print program or process to manufacture the part to beprinted. The slicing process may execute or transmit the print programto CNC machine 1 to print or otherwise manufacture the part.

The slicing process may be executed by a user via controller 100 of CNCmachine 1 or an external computing device having a controller, e.g., aprocessor or microprocessor. Exemplary computing devices include, butare not limited to, a desktop computer or workstation, a laptopcomputer, a mobile handset, a personal digital assistant (“PDA”), asmart phone, a server, or any combination of these or other computingdevices having a display, at least one controller (e.g. a processor ormicroprocessor), a memory, and one or more input devices. The user inputdevice(s) may include any type or combination of input/output devices,such as, e.g., a keyboard, a touchpad, a mouse, a touchscreen, a camera,a stylus, and/or a scanner (e.g., a laser scanner).

The disclosed slicing process may include a user viewing, inputting, orotherwise executing the slicing process via a graphical user interface(“GUI” or “interface”) displayed by controller 100 (e.g., via display101) and/or another electronic device. The interface may include one orprompts and/or other elements allowing or requesting that the user toinput, select, or otherwise determine parameters of the slicing process.Prompts for user input may include, but are not limited to, links,buttons, images, check boxes, radio buttons, text boxes, and menus. Asused herein, a print parameter referred to as “a selection” by the usermay include the user selecting a value from a number of preset values,checking a check box, clicking a radio button, or otherwise making aselection using one or more prompts.

Turning now to FIG. 4, an interface 400 may present the user with a partmodel viewer and a part model slice viewer. The part model viewer mayallow the user to digitally assemble a part model of the individualsections of a part to be printed, or of the whole part (e.g., includingthe individual sections merged together). The part model slice viewermay allow the user to view the CAD model slice-by-slice for each sectionor the part to be produced as a whole. Additionally, the part modelslice viewer may permit the user to view a net model, a print tool path,or a physical print beads model of the section or part to be printed.The user may reference the print model viewer and/or the part modelslice viewer before, during, or after executing the slicing process.

Interface 400 may include a prompt, e.g., an additive manufacturingtoolbar 402, for a user to select a toolpath type and/or otherparameters of the slicing and printing processes. The toolpath types mayspecify the slicing process corresponding to the CAD model(s). Thetoolpath types may further define how the CAD model(s)of the part to beprinted are divided into sections, and how each section is furtherdivided into layers via the slicing process. Exemplary tool path typesmay include an AM Slice type, an AM Outline type, and an AM SurfaceOutline type. The AM Slice toolpath type may specify that the slicingprocess includes dividing a CAD model of solids, surfaces, or polygonalmesh into cross sectional layers, each layer having a thicknessdetermined in part based on the layer height (e.g., spacing) printingparameter. The AM Outline toolpath type may specify that the slicingprocess includes receiving a 2D line drawing of the part or section toproduce a layer or multiple layers that follow the path of the linedrawing. Using the AM Outline toolpath type, the total number of layersand layer height produced by the slicing process may be determined baseda parameter input by the user. The AM Surface toolpath type may specifythat the CAD model(s) include a 2D line drawing of the part or section,and that the drawing is divided into a layer or multiple layers thatfollow the path of the solids, surfaces, or polygonal mesh. The numberof layers in height produced by the AM Surface Outline toolpath type maybe determined based on a height of the section or part. Interface 400may include an AM Z Merge selection for combining toolpaths. The AM ZLayer Merge selection may combine each of the different toolpaths (andtheir respective print parameters) as generated by the slicing processinto a single printing process for all sections and/or layers of thepart to be printed. Thus, the slicing process may receive electronicmodels, e.g., CAD models, having multiple types of geometries, such as,e.g., solids, surfaces, polygonal mesh, and 2D drawings to produceand/or execute a printing process for manufacturing the part.

Once the toolpath type has been selected, a category of print parametersmay be selected. The categories of print parameters may include, but arenot limited to, general, boundary, and fill. In some examples, theselected tool path type may determine the print parameter categoriesthat may be defined by the user. For example, the AM Outline and/or AMSurface Outline may not include a fill category.

FIG. 5 depicts a user interface 500 prompting the user to input valuesor otherwise specify the print parameters of a geometry subcategorywithin the general category. The geometry subcategory may include printparameters such as a tessellation chord tolerance parameter, acontainment boundaries parameter, a Z limits parameter, a toolpath startlocations parameter, and a seam avoidance offset parameter. Thetessellation chord tolerance parameter is a value indicative of theaccuracy with which the toolpath follows the contour of the section orpart. In some examples, the tessellation chord tolerance parameter maybe changed or selected so as to smooth the toolpaths, e.g., byincreasing the tessellation chord tolerance parameter. The containmentboundaries parameter refers to an inside surface and an outside surfaceof the part. The area formed between the inside surface and the outsidesurface may be referred to as the “fill.” For example, a donut shapedsection may include an inner circle corresponding to the inner surface(e.g., the hole), an outer circle circumferentially surrounding theinner circle and corresponding to the outer surface, and an area formedbetween the inner circle and the outer circle corresponding to the fill.In some examples, the containment boundaries may have differentthicknesses in different areas. For example, with reference to FIG. 6, apart 600 may include a top side 604 having six boundary layers and abottom side 602 including two boundary layers.

Turning back to FIG. 5, the Z Limits print parameters may include alower Z material limit and an upper Z material limit. Additionally oralternatively, the interface may include a full part parameter which maybe selected so that the lower Z material limit is set at a bottomsurface of the section being printed and an upper Z material limitdefined a distance from the bottom surface to a surface having thegreatest height from the bottom surface. The distance between the lowerZ material limit and the upper Z material limit may define a range ofheights for which layers of the section may be determined by the slicingprocess. The Z limits print parameters may enable users to select anentire electronic model (e.g., CAD model/drawing) of a part or a sectionof the part defined between the lower Z material limit and the upper Zmaterial limit for processing via the slicing process. For example, thesection of the CAD model may be defined as any portion of the CAD modelhaving a height above the worktable 27 that is 2 inches to 6 inches.Additionally or alternatively, the Z limit print parameters may bedefined so that different printing parameters may be applied to separateheights of the same section. For example a part 700 shown in FIGS. 7Aand 7B includes a bottom section 701, a middle section 702, and a topsection 701, each section defined by Z limits print parameters ofvarying heights. Further, each of the bottom section 701, the middlesection 702, and the top section 703 has different print parameters,e.g., different boundary layers and fill styles. The bottom section 701has two boundary layers with a fill between the boundary layers. Themiddle section 702 has two boundary layers. The top section 703 has onlyone boundary layer.

With reference again to FIG. 5, the start point location set of printparameters may include an open toolpath parameter, a close toolpathparameter, and a seam avoidance offset parameter. The open toolpathparameter and the closed toolpath parameter allow the user to selectgeometry to define where the toolpath starts on any given layer. Theseam avoidance offset parameter is a distance a start and a stop seamlocation are offset from one another between print layers.

In addition to the geometry subcategory, the general category mayinclude a toolpath subcategory. FIG. 8 shows an exemplary interface 800through which a user may input values for the print parameters includedin the toolpath subcategory. The toolpath subcategory may include printparameters or sets of print parameters such as, e.g., a slice planeparameter, a merge slices for extra stock parameter, an ignore innercontours parameter, a layer order parameter, a layer height (spacing)parameter, a contact tip—workpiece parameter, an outer stock to leave(2D) parameter, an inner stock to leave (2D) parameter, an arc chordtolerance parameter, a clearance height parameter, an initial clearheight parameter, and a combine stock offset with toolpath offsetsparameter. The slice plane parameter defines a plane from which the CADmodel will be sliced. The slice plane parameter may be selected from anumber of preset values, such as, e.g., top, side, etc. Additionally oralternatively, the slice plane parameter may be determined by controller100 or input by the user. The merge slices for extra stock parameter maycompare an outline of a slice of a layer selected by the user (the“selected layer”) to an outline of a layer on which the selected layerwill be applied (the “previous layer”) and an outline of a layer thatwill be applied on top of the selected layer (the “subsequent layer”).The merge slices for extra stock parameter may then select the outlinehaving the greatest surface area among the selected layer, the previouslayer, and the subsequent layer for use in producing the toolpath forthe current layer. The ignore inner contours parameter may be aselection of whether or not the inner contours are removed fromconsideration during the slicing process. The layer order set of printparameters may be a selection of whether the boundary or fill of eachlayer is deposited first. The layer height (spacing) print parameterdefines a measurement of a thickness of each layer to be produced by theslicing process. The contact tip—workpiece parameter is a distance aboveworktable 27 at which the applicator head 43 is positioned beforebeginning the printing process.

With continued reference to FIG. 8, the contact—tip workpiece parameteris measured relative to the Z limits. For example, if the lower Zmaterial limit is defined as 2 inches, a value of −2 inches may be inputto define the contact tip-workpiece print parameter to position theapplicator head 43 on the worktable 27, instead of 2 inches above theworktable 27, when beginning the print process. The outer stock to leave(2D) parameter is a distance the bead being deposited is offset from anoutside surface of the outside contour of the section being printed. Theinner stock to leave parameter is a distance the bead being deposited isoffset from an inside surface of the inside contour of the section. Thearc chord tolerance parameter is a distance controlling the fit of thearcs of the applicator head 43 to the toolpath. In some examples, thearc chord tolerance parameter may be adjusted or selected to smooth outthe toolpath. For example, decreasing the value of the arc chordtolerance may produce arcs over the toolpath having a smoother shape.The clearance height parameter is a height above worktable 27. Theapplicator head 43 moves to this height between printing separatelayers. The initial clearance height parameter is a height aboveworktable 27 to which applicator head 43 moves before initiating theprinting process. The combine stock offset with toolpath offsetparameter is a selection that determines whether the distances of thestock offset and the toolpath offset are combined into a single valuewhen executing the slicing process.

FIG. 9 depicts a user interface 900 that allows the user to input valuesor otherwise specify print parameters included in the processsubcategory of the general category. Exemplary print parameters withinthe process subcategory include a rafts parameter, a stock on topparameter, a melt settings parameter, a void detection parameter, apull-back parameter, and a smoothing parameter. The rafts parameterrefers to a number of layers printed before the layers of the part orsection being printed are deposited. For example, if the rafts parameteris a value of 2, the applicator head 43 will deposit 2 layers beforedepositing the first layer of the part or section being printed. Thestock on top parameter is a number of layers printed on a top layer ofthe part or section or part being printed. The top layer is the layerhaving the greatest Z axis height of the part or section. The top layerdoes not refer to peak areas of the part or section, e.g., an area of alayer having a height less than another layer, wherein no layers aredeposited on top of the area. For example, a part may have a middlelayer below the top layer. The middle layer may include a peak, e.g., aportion of the middle layer where no material is deposited. In thisexample, the stock on top parameter defines the number of layersdeposited only on the top layer even though no layers will be depositedon the middle layer at the peak. The melt settings parameter defines thepercentage by which the speed of the gear pump (measured in RPM) isreduced on overlapping beads during operation of the CNC machine 1. Themelt setting print parameter may be changed to reduce buildup fromdepositing one bead adjacent to the next. The void detection set ofprint parameters refer to parameters that define the fill for any voidsdetected during an analysis of the layers of the part or sectionperformed during the slicing process.

The pull-back parameters include a selection of whether or not to take apull-back process into account when executing the slicing process, andthe corresponding parameters for that pull-back process. A pull-backprocess may be used to avoid removing excess material from corners ofthe part. In some examples, if a pull-back process is not used whenprinting a corner of a part the roller 59 may disengage from the bead.Then, when the roller 59 reengages with the bead, the roller 59 mayinadvertently push material away from the corner. The pull-back lengthparameter is a distance from a corner at which the pull-back process maybegin. Upon reaching the distance from the corner specified by thepull-back length parameter, the roller 59 may be moved away from thecorner by the distance input for the pull-back extensions parameter. Insome examples, pull-back may be referred to as “corner-pull-back.” Thesmoothing print parameters may include a maintain smooth curvesparameter, a remove small polygons parameter, a never start in a cornerparameter, and a minimum polygon angle parameter. The smoothing printparameters may alter or adjust the toolpaths of a part or section tosmooth any curves.

FIG. 10 depicts a user interface 1000 that allows the user to inputvalues or otherwise specify the print parameters included in the toolsubcategory under the general category. The tool subcategory mayrepresent the melt configuration corresponding to the tool used in theprinting process. For example, a melt configuration number 1 maycorrespond to a tool number 1, where melt configuration 1 is describedas using a print material comprising 20% carbon fiber filled ABS, aprint bead width of 0.83 inches and a print bead thickness of 0.20inches.

FIG. 11 depicts a user interface 1100 that allows the user to input,select, or otherwise specify the values of the print parameters includedin the passes subcategory under the boundary category. The passessubcategory may include print parameters or sets of print parameterssuch as, e.g., a program boundary passes parameter, an inside-out passesparameter, a reverse direction on alternating layers parameter, a numberof beads parameter, a pass overlap parameter, a maximum pass overlapparameter, a start/stop overlap parameter, a minimum pass lengthparameter, a lead-in length parameter, a lead-out length parameter, aforce tangential lead-out parameter, and a thin wall sections parameter.The program boundary passes parameter refers a selection of whether ornot the toolpath includes boundary passes. The inside-out passesparameter is a selection of whether or not the toolpath starts with aninner-most pass, determined with respect to the layer outline, andprogress outwards towards the layer outline. The reverse direction onalternating layers parameter is a selection of whether or not thetoolpath reverses direction for every other layer.

The number of beads parameter represents the number of toolpath passesto made by the applicator head 43 along each boundary of the layeroutline. The pass overlap parameter specifies a value of the lowestpercentage of overlap between adjacent beads (measured as a percentageof the bead width). The maximum pass overlap parameter refers to amaximum distance (measured as a percentage of the bead width) thatadjacent print beads will overlap one another. The start/stop overlapparameter is a value corresponding to the percentage of overlap betweenthe beginning and ending of the bead on boundary passes (measured as apercentage of bead width). The lead-in length parameter is a distancethat the bead will be deposited along a layer before starting to depositeach boundary pass. The lead-out length parameter is a distance the beadwill be deposited measured from the end of each boundary pass. The forcetangential lead-out print parameter is a selection determining whetherthe bead moves tangentially to the toolpath upon completing thetoolpath. The thin wall sections set of print parameters may include amaximum width parameter, a search for and fill thin wall sectionsparameter, a maximum width for one bead parameter, a maximum thicknessdeviation parameter, a maximum stitching gap parameter, a maximumintersection distance parameter, an auto calculate parameter, and anequals bead width parameter. As defined herein, a thin wall is a portionof a layer of the section or part being printing between two boundariespositioned close to one another. In other words, the two boundaries forma thin wall between them. The set of thin wall sections set of printparameters may be used to identify a thin wall area in a section orsection and if and/or how such an area should be filled.

FIG. 12 depicts a user interface 1200 that allows the user to inputvalues or otherwise specify print parameters included in the processsubcategory under the boundary category. In some examples the processsubcategory for the fill category include the same print parameters asthe boundary category. The print parameters of the process subcategorymay include a travel speed parameter, a melt on settings set of printparameters, and a melt off settings set of print parameters. The travelspeed parameter is a maximum feed rate of the flowable material throughthe applicator head as it deposits material. The melt on settings set ofprint parameters may include a prime melt when turning on parameter, adelay during priming parameter, a prime time parameter, and a primingRPM parameter. The prime melt when turning on parameter is a selectionof whether or not the priming process is executed before depositing eachbead. The delay during priming parameter is a selection of whether ornot the bead may be deposited along the toolpath during the primingprocess. The priming time parameter is period of time for which thepriming process may be executed. The priming RPM parameter is a speed,measured in revolutions per minute, at which the extruder 61 rotates theextruder screw during the priming process.

The melt off settings set of print parameters may include an apply coastoff motion parameter, a coast distance parameter, a reverse melt whenturning off parameter, an apply reverse during coast motion parameter, adelay during reverse parameter, a reverse time parameter, and a reverseRPM parameter. The melt off settings set of parameters control theextrusion and/or deposition of material during a “coast process”executed at the end of printing each bead. The apply coast off motionparameter is a selection of whether or not the extruder continues tomelt the material while the applicator head 43 moves through distancespecified by the coast distance parameter. The coast distance parametera distance, measured from the end of each bead, that the applicator head43 moves while executing the coast process. The reverse melt whenturning off parameter is a selection of whether or not the to reversethe flow of material during the coasting process. The flow of materialmay be reversed while the applicator head 43 moves through the coastdistance, or while the applicator head 43 stays in place. In someexamples, the flow may be reversed by rotating the extruder screw and/orthe gear pump 62 in a direction opposite to the direction of rotationfor printing. Reversing the flow of material may, in some embodiments,pull material into one or more parts of CNC machine 1, e.g., theextruder 61 or the applicator head 43.

The apply reverse during coast motion parameter is a selection thatcontrols whether the reversal of the flow of the material is reversedwhile the applicator head 43 moves through the coast distance. The delayduring reverse parameter is a selection determining whether the reversalof the flow of the material is time bound by the reverse time parameter.The reverse time parameter is a period of time that the flow is reversedduring the coasting process. The reverse RPM parameter is a speed(measured in revolutions per minute) that the extruder screw is rotatedwhen the flow of the material is reversed. The set at control parameteris a selection of whether or not the priming time parameter, the primingRPM parameter, the reverse time parameter, or the reverse RPM parametermay be overridden by the slicing process and replaced with valuesreceived via command codes determined by the controller 100.

FIG. 13 depicts a user interface 1300 that allows the user to inputvalues or otherwise specify the print parameters included in the beadgeometry subcategory under the boundary category. In some examples, thebead geometry subcategory under the fill category may include the sameprint parameters as the geometry subcategory of the boundary category.The parameters listed on this subcategory may include a bead heightcontrolled by layer height parameter and a width parameter.

The bead height controlled by layer height parameter is a thickness ofeach bead being deposited to form each layer of the section or part. Thebead height controlled by layer height parameter may be determined basedin part on the layer height parameter of the toolpath subcategory of thegeneral category. The width parameter is a measurement of a width of thebead to be deposited. The width parameter may be used to generate thetoolpath and/or simulate the printing process. As mentioned above, oneor more of the print parameters may be determined based in part on thevalue of the width parameter.

FIG. 14 depicts a user interface that allows the user to input values orotherwise specify the print parameters included in the passessubcategory under the fill category. The passes subcategory may includeprint parameters such as, e.g., a program fill passes parameter, a fillstyle parameter, a linking passes with rapids parameter, an optimize tosurface features parameter, a pass overlap parameter, a maximum sparsefill spacing parameter, a maximum pass overlap parameter, a boundaryoverlap parameter, a boundary side overlap parameter, a starting fillangle parameter, a change in angle per layer parameter, a minimum filllength parameter, a lead-in length parameter, a lead-out lengthparameter. The program fill passes print parameter is a value indicatinga selection of whether or not the toolpath will be determined with afill. The fill style parameter is a selection of the method ofdetermining the toolpath for the fill. Exemplary fill styles include asimple zigzag style, a smart zigzag style, a smart zigzag constantoverlap style, a variable bead regions style, a sparse zigzag style.These exemplary fill styles are illustrated in FIGS. 15 through 19,which will now be described.

FIG. 15 depicts a top view diagram of the toolpath of a layer 150produced using the one way fill style. The one way fill style mayproduce a toolpath having lines all oriented along the same direction.The toolpath begins by depositing a bead in a first pass starting at afirst point 151 moving along a first vector 153 toward a second point152. Upon reaching point 152, the applicator head 43 stops depositingthe bead, and moves to a third point 156 adjacent to the start of thefirst pass, at first point 151. The bead then deposits a second passfrom the third point, the second pass extending along the first vector153 adjacent to the first pass. These steps are repeated to depositadditional passes, each subsequent pass being depositing along the firstvector 153 adjacent to the preceding pass. Accordingly, a width of eachpass of the toolpath increases a width of the layer 150 along a secondvector 154. If the applicator head 43 encounters a hole 155 in layer150, e.g., at point 157, the applicator head 43 stops printing the beadand moves to a position across the hole 155 opposite of point 157, point158,. The applicator head 43 then continues to deposit the printing beadalong the first vector 153. Once the pass containing points 157 and 158is completed, the applicator head 43moves to a position 159 adjacent thestart of the pass that contains points 157 and 158. The applicator head43 continues to deposit the printing bead in this manner until the layer150 is complete.

FIG. 16 depicts a top view diagram of the toolpath of a layer 160generated using the simple zigzag fill style prints. The simple zigzagfill style may produce a toolpath that serpentines along the layer tofill the layer. For example, the toolpath may begin a first pass at afirst point 161 and extend along a first vector 163. Upon reaching aboundary of the layer 160, the first pass may be completed, but the beadmay still be deposited as the applicator head 43 moves along a secondvector 164 a distance equal to the width of the bead being depositedalong the tool path. The toolpath then begins a second pass, guiding theapplicator head 43 in a direction opposite the first vector 163 till itreaches another boundary of the layer. By these steps, the bead isdeposited in a serpentine manner in which each subsequent pass extendsadjacent to the preceding pass in a direction opposite the precedingpass. If the toolpath encounters a hole 165 in the layer 160, e.g., at asecond point 166, the applicator head 43 stops depositing the bead andcontinues to follow the current pass direction over the hole till theapplicator head 43 has completely passed over the hole, e.g., at a thirdpoint 167. The applicator head 43 then begins depositing the bead ofmaterial from the third point 167 in the same manner as the previouspasses. The steps of stopping the printing of the bead and moving overthe hole 165 may be repeated for any additional points where thetoolpath intersects the hole 165, e.g., from a fourth point 168 to afifth point 169.

FIG. 17 depicts a top view diagram of the toolpath of a layer 170generated using the smart zigzag fill style. The toolpath generatedusing the smart zigzag fill style is generated in a manner similar tothe simple zig zag fill style. For example, a first pass may begin at afirst point 171 and extend along a first vector 173. The toolpath mayserpentine through the layer 170 along a second vector 174 whilecontinuously depositing material. Using the smart zigzag fill style, ifthe toolpath intersects a hole 175 the applicator head 43 will continueto serpentine along the second vector 174 without passing over the hole175 until the toolpath reaches a second point 172, where the toolpathintersects the hole 175 along the pass furthest along the second vector174. At the second point 172, the applicator head 43 may stop depositingmaterial and move to a third point 176 adjacent to the start of the mostrecent pass that intersected the hole 175. After reaching an end pointof the layer 170 along the second vector 174, e.g., at a fourth point177, the applicator head 43 stops depositing material and moves to apoint along the last path that intersected the hole 175. This fifthpoint 178 is opposite the second point 172. From the fifth point 178,the toolpath may serpentine between the hole 175 and the outline of thelayer 170 in a direction opposite to the direction of the second vector174. The toolpath continues until it reaches a sixth point 179 where thenext would intersect a previously deposited pass.

FIG. 18 illustrates a part 180 manufactured using the constant overlapfill style. The constant overlap fill style produces a toolpath in thesame general manner as the smart zigzag fill style. However the constantoverlap fill style creates a toolpath having a constant percentage,measured with respect to the bead of material, of overlap between passesof the toolpath. In some examples, sections or parts, e.g., sections orparts without a cavity or hole therein, may be printed with a toolpathlimited to the fill of the part. In further examples, sections or partsmay be printed from toolpaths absent boundary beads.

FIG. 19, illustrates a top view diagram of the toolpath of a layer 190generated using the sparse zigzag fill type. Under the sparse zigzagfill type, a first pass may begin at a first point 191 and extend alonga first vector 193. The toolpath may serpentine across the layer 190 inthe direction of a second vector 194. As shown, the serpentine shape ofthe toolpath may leave a space between curves of the toolpath. If thetoolpath intersects a hole 195 the toolpath will continue to serpentinealong the second vector 194 between the hole 195 and a boundary of thelayer. The toolpath continues along the layer in the direction of thesecond vector 194 until reaching an second point 192. Upon reaching thesecond point 192, the toolpath may instruct the applicator head 43 tostop depositing material and move to a space on the layer that has notyet been filled, e.g., a third point 196. The toolpath may includedirections to deposit material from the third point 196 and move theapplicator head 43 in along a direction opposite the second vector in aserpentine manner till the toolpath reaches a fourth point 197. Thefourth point 197 may be a position adjacent to a bead of material thathas already been deposited along the toolpath. The toolpath may furtherinclude one or more passes along any spaces or gaps between the curvesof the toolpath, e.g., a pass beginning at a fifth point 198.

The variable bead regions fill style (not shown) may include determininga toolpath in a similar fashion to the smart zigzag tool type, thetoolpath being altered to include an extra pass to fill any voidsdetected between the bead of the fill and a boundary of the layer.

With reference again to FIG. 14, the linking passes with rapidsparameter a selection that determines whether the material is stillmelted, e.g., by operating the extruder 61, when the applicator head 43moves from one fill line or pass to the next. Optimize to surfacefeatures is a selection of whether or not the toolpath is generatedweighing accuracy of adhering to the contours of the part over reducingoverlap between beads. The pass overlap parameter is a minimumpercentage that the bead being deposited will overlap adjacent beadsthat have already been deposited as determined as a percentage of thewidth of the bead of the boundary. The maximum sparse fill spacingparameter is a maximum distance allowed between a center of one bead tothe center of the adjacent bead when using the sparse zigzag fill style.The maximum pass overlap parameter is a maximum allowed percentage,measured with respect to the width of bead of the fill, that the beadcan overlap adjacent beads. The boundary overlap parameter is apercentage, measured with respect to the bead width of the boundary,that each bead of the fill near the periphery of the layer may overlapthe boundary beads of the layer. The value of the boundary overlapparameter may be input as a percentage of the width of the bead of theboundary. The boundary side overlap parameter is aa percentage measuredwith respect to the bead width of the boundary, that each bead of thefill that contacts the boundary will overlap the bead of the boundary.The starting fill angle parameter is an angle of the initial fill layer.The change in angle per layer parameter is angle the subsequent filllayer will be printed on with respect to the previous fill layer. Theminimum fill length parameter is a minimum distance the toolpath mustextend to be included as a fill pass. The lead-in length parameter is adistance used to approach the start of each fill pass. The lead-outlength print parameter is a distance that the bead of the fill isdeposited extending from the end of each fill pass along the toolpath.The force tangential lead-out is a distance the bead of the fill willextend tangentially from the last point in the toolpath.

FIG. 20 depicts a user interface 200 that allows the user to inputvalues or otherwise specify the print parameters included in the fillstyle print parameters subcategory. The parameters listed on the fillstyle print parameters subcategory may include a fillet radius on pathcorners parameter, a melt output reduction in corners parameter, atravel speed on corners parameter, a max end overlap distance parameter,a max side overlap distance parameter, a place fill turns outsidesection boundary parameter, a limit to fill line matching parameter, afill line extension before turn set of parameters, a step toleranceparameter, and an angle tolerance parameter. The fillet radius on pathcorners parameter is a percentage of a radius of the bead at each cornerof toolpath within the fill. The melt output reduction in cornersparameter is a percentage of reduction of material being output incorners. The travel speed on corners parameter is a speed the nozzle 51travels in the corners which can be made to match the fill pass speed bychecking the parameter same as fill passes travel speed. The max endoverlap distance parameter is a maximum distance the end of a fill beadcan cross into a boundary bead and is used in conjunction with boundaryoverlap. The max side overlap distance parameter is a maximum distancethe side of a fill bead can cross into a boundary bead and is used inconjunction with boundary side overlap. The place fill turns outsidepart boundary parameter is a selection to determine whether the toolpathline extends beyond the fill boundary at turns of the toolpath. When noboundary passes are included, if the two fill lines involved in a bridgedo not form a perpendicular bridge, the shorter fill line is extended tobe even with the longer fill line. If the difference in the two fillline end points is greater than the limit to fill matching value, theshorter fill line will not be extended and no bridge will be formed.

With continued reference to FIG. 20, the fill line extension before turnoption allows the ends of each fill pass to be extended by a distancebeyond the part boundary. The step tolerance parameter is a distancethat is referenced for scale when determining the fill of small entitiesat a top and a bottom of a fill surface. The angle tolerance parameteris an angle indicative of the margin of error in creating a flatsurface, e.g., the top surface and bottom surface of the fill surface.

Based in part on one or more of the foregoing print parameters, theslicing process may divide an electronic model(s), e.g., a CAD model, ofthe part to be printed into a number of sections, each section havingone or more layers, and each layer having a distinct toolpath and printparameters. The slicing process may produce a print program or processbased in part on the sections and/or layers. The print program may betransmitted to CNC machine 1 to manufacture the part. FIG. 21 shows anexemplary flow diagram of a method 300 of executing the slicing processand manufacturing a part. The slicing process may include receiving anelectronic model, such as, e.g., a CAD model, at an electronic device(e.g., at controller 100) at a step 302. Next, at a step 304, the modelmay be divided into a number of sections. Before slicing each sectioninto layers, the parameters for printing those layers may be input,selected, adjusted, or otherwise specified by a user and/or retrievedfrom memory by the slicing process. To begin defining the parameters ofeach section, a toolpath type may be selected at a step 306. Next, at astep 308, a category of print parameters may be defined. Then, asubcategory of print parameters may be defined at a step 310. At step312, one or more print parameters for the section may be defined. Steps308, 310, and 312 may be repeated as desired to define print parametersunder different categories or subcategories and/or print parameters ofdifferent sections. At step 314, the slicing process may slice or dividethe sections into a number of layers. At step 316, the slicing programmay produce a printing program or process to be executed at the CNCmachine 1. The printing program may include some or all of the layersand sections of the part to be manufactured. Then, at step 318, theslicing process may initiate manufacturing of the part. The method 300shown in FIG. 21 is only exemplary. Some of all of the steps of method300 may be completed. Additionally or alternatively, the steps of method300 may be executed in a different sequence.

The printing process to manufacture the part produced by the slicingprocess may print a first layer of a first section in a manner such thatthe first layer overlaps, contacts, and/or meshes with a first layer ofa second section. In some examples, the separate sections of themanufactured part may be printed by the CNC machine 1 so that thesections meld, join, or otherwise attach to one another. That is, incontrast to the formation of separate portions which are subsequentlyassembled to form a part, the methods described herein permit each ofthe separate sections of a part to be printed in a single printingprocess to form the part.

From the foregoing detailed description, it will be evident that thereare a number of changes, adaptations and modifications of the presentdisclosure which come within the province of those persons havingordinary skill in the art to which the aforementioned disclosurepertains. However, it is intended that all such variations not departingfrom the spirit of the disclosure be considered as within the scopethereof as limited by the appended claims.

1. A method of forming a part using additive manufacturing, the methodcomprising: receiving, at a computer numeric controlled (CNC) machine, acomputer aided design (CAD) model of the part; dividing the CAD modelinto a plurality of sections including a first section and a secondsection, the first section and the second section being determined basedon a first height range and a second height range, respectively;selecting, by user inputs, a first set of print parameters for the firstsection and a second set of print parameters for the second section,wherein the first set of print parameters are different from the secondset of print parameters, wherein the first set of print parametersinclude an overlap parameter that defines an amount of overlap ofadjacent beads of material; slicing each of the plurality of sectionsinto a plurality of layers after selecting the first set of printparameters and the second set of print parameters; depositing a flowablematerial onto a worktable according the set of print parameters for eachsection of the of the plurality of sections to manufacture the partincluding depositing adjacent beads of the flowable material thatoverlap each other according to the amount of overlap defined by theoverlap parameter.
 2. The method of claim 1, wherein dividing the CADmodel into the plurality of sections includes defining one sectionhaving a lower most layer positioned at a height above the worktable. 3.The method of claim 1, wherein the sets of print parameters includes atoolpath type for each of the plurality of layers.
 4. The method ofclaim 3, wherein the sets of print parameters include a fill style, thefill style including a smart zigzag type.
 5. The method of claim 1,wherein depositing the flowable material includes printing a first layerof the first section and a first layer of the second section, andwherein the first layer of the first section and the first layer of thesecond section fuse together.
 6. The method of claim 1, wherein thelayers of the first section are deposited so as to be interspersed withthe layers of the second section.
 7. A method of forming a part usingadditive manufacturing, the method comprising: receiving at anelectronic device, a computer aided design (CAD) model of the part;dividing the CAD model into a first section and a second section basedon a first height range and a second height range, respectively;selecting, by a user input, a first set of print parameters for thefirst section including an overlap parameter that defines an amount ofoverlap of adjacent beads of material; selecting, by a user input, asecond set of print parameters for the second section, wherein the firstset of print parameters is different from the second set of printparameters; slicing the first section into a first set of layers andslicing the second section into a second set of layers after selectingthe first set of print parameters and the second set of printparameters; and depositing a flowable material onto a surface accordingthe first set of print parameters and the second set of printparameters, wherein the first set of layers and the second set of layersare deposited so as to be interspersed with one another.
 8. The methodof claim 7, wherein depositing the flowable material onto the surfaceincludes forming the first section and the second section, the firstsection fusing to the second section.
 9. The method of claim 7, whereinthe first set of layers includes a first layer, the first layer having afirst height above the surface, wherein the first height is spaced abovethe surface.
 10. The method of claim 7, wherein the flowable material isdeposited according to the first set of print parameters and the secondset of print parameters in a single printing process.
 11. (canceled) 12.The method of claim 7, wherein the first set of layers includes a fillportion and a first boundary bead, and the second set of layers includesa second boundary bead, and wherein the second set of layers do notinclude a fill portion.
 13. A method of forming a part using additivemanufacturing, the method comprising: receiving at an electronic device,a computer aided design (CAD) model of the part; dividing the CAD modelinto a plurality of sections including a first section and a secondsection, the first section and the second section being determined basedon a first height range and a second height range, respectively;selecting a first set of print parameters for the first section,including an overlap parameter that defines an amount of overlap ofadjacent beads of material, and a second set of print parameters for thesecond section; slicing each of the plurality of sections into aplurality of layers after selecting the first set of print parametersand the second set of print parameters, each layer having a plurality ofprint parameters; and depositing a flowable material onto a substrateaccording to the plurality of print parameters for each of the pluralityof layers, including depositing adjacent beads of the flowable materialthat overlap each other according to the amount of overlap defined bythe overlap parameter, wherein the first set of print parameters differsfrom the second set of print parameters.
 14. The method of claim 13,wherein the electronic device is a computer numeric controlled (CNC)machine.
 15. The method of claim 13, wherein the plurality of printparameters of the set of layers of the first section include an upper Zmaterial limit and a lower Z material limit, the lower Z material limithaving a height above the substrate.
 16. The method of claim 13, whereina number of the plurality of layers is determined based in part on aheight of one or more of the plurality of sections.
 17. The method ofclaim 13, wherein the first section includes a number of boundary layersdifferent from a number of boundary layers of the second section. 18.(canceled)
 19. The method of claim 13, wherein the layers of the firstsection and the layers of the second section are deposited so as to beinterspersed with one another, and wherein one or more of the layers ofthe first section fuses with one or more of the layers of the secondsection.
 20. The method of claim 13, wherein the CAD model includes ashape of an outer surface of the part and a shape of an internalstructure of the part.
 21. The method of claim 1, wherein the first setof print parameters includes a layer height parameter, the layer heightparameter defining a thickness of each layer produced in the slicing.22. (canceled)
 23. The method of claim 1, wherein the overlap parametercorresponds to a lowest amount of overlap of the adjacent beads ofmaterial or a maximum amount of overlap of the adjacent beads ofmaterial.